Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Intracavity electromagnetically induced transparency in atoms around a nanofiber with a pair of Bragg grating mirrors

Fam Le Kien, K. Hakuta

Published Apr 15, 2009• 28 citations
Publisher

Abstract

We study intracavity electromagnetically induced transparency in atoms around a nanofiber with a pair of Bragg grating mirrors. We calculate the transmission of the composite cavity-fiber-atom system and the time development of the guided probe light field. We derive analytical approximate expressions for the output probe field and its group delay. We show that the group delay of the guided light substantially depends on the input pulse length, the mirror reflectivity, the atomic number density, and the coupling field intensity. We demonstrate that the group delay of the guided light can be significantly enhanced by the presence of the fiber-Bragg-grating cavity even when the finesse of the cavity is moderate.

DOI
10.1103/physreva.79.043813

Related papers

Electromagnetically induced transparency for guided light in an atomic array outside an optical nanofiber

Fam Le Kien, Arno Rauschenbeutel

We study the propagation of guided light along an array of three-level atoms in the vicinity of an optical nanofiber under the condition of electromagnetically induced transparency. We examine two schemes of atomic levels and field polarizations where the guided probe field is quasilinearly polarized along the major or minor principal axis, which is parallel or perpendicular, respectively, to the radial direction of the atomic position. Our numerical calculations indicate that 200 cesium atoms in a linear array with a length of 100 $\ensuremath{\mu}\mathrm{m}$ at a distance of 200 nm from the surface of a nanofiber with a radius of 250 nm can slow down the speed of guided probe light by a factor of about $3.5\ifmmode\times\else\texttimes\fi{}{10}^{6}$ (the corresponding group delay is about 1.17 $\ensuremath{\mu}\mathrm{s})$. In the neighborhood of the Bragg resonance, a significant fraction of the guided probe light can be reflected back with a negative group delay. The reflectivity and the group delay of the reflected field do not depend on the propagation direction of the probe field. However, when the input guided light is quasilinearly polarized along the major principal axis, the transmittivity and the group delay of the transmitted field substantially depend on the propagation direction of the probe field. Under the Bragg resonance condition, an array of atoms prepared in an appropriate internal state can transmit guided light polarized along the major principal in one specific direction even in the limit of infinitely large atom numbers. The directionality of transmission of guided light through the array of atoms is a consequence of the existence of a longitudinal component of the guided light field as well as the ellipticity of both the field polarization and the atomic dipole vector.

arXiv:1502.04151•Physical Review A•May 22, 2015•29 citations

Cavity-enhanced channeling of emission from an atom into a nanofiber

Fam Le Kien, K. Hakuta

We study spontaneous emission of an atom near a nanofiber with two fiber-Bragg-grating (FBG) mirrors. We show that the coupling between the atom and the guided modes of the nanofiber can be significantly enhanced by the FBG cavity even when the cavity finesse is moderate. We find that, when the fiber radius is 200 nm and the cavity finesse is about 30, up to 94% of spontaneous emission from the atom can be channeled into the guided modes in the overdamped-cavity regime. We show numerically and analytically that vacuum Rabi oscillations and strong coupling can occur in the FBG cavity even when the cavity finesse is moderate (about 30) and the cavity length is large (on the order of 10 cm to 1 m), unlike the case of planar and curved Fabry-Perot cavities.

arXiv:0910.5276•Physical Review A•Nov 24, 2009•80 citations

Effect of an atom on a quantum guided field in a weakly driven fiber-Bragg-grating cavity

Fam Le Kien, K. Hakuta

We study the interaction of an atom with a quantum guided field in a weakly driven fiber-Bragg-grating (FBG) cavity. We present an effective Hamiltonian and derive the density-matrix equations for the combined atom-cavity system. We calculate the mean photon number, the second-order photon correlation function, and the atomic excited-state population. We show that due to the confinement of the guided cavity field in the fiber cross-section plane and in the space between the FBG mirrors, the presence of the atom in the FBG cavity can significantly affect the mean photon number and the photon statistics even though the cavity finesse is moderate, the cavity is long, and the probe field is weak.

arXiv:1001.5308•Physical Review A•Feb 12, 2010•9 citations

Triggered generation of single guided photons from a single atom in a nanofiber cavity

Fam Le Kien, K. Hakuta

We study the deterministic generation of single guided-mode photons from an atom in the vicinity of a nanofiber with two fiber-Bragg-grating (FBG) mirrors. The technique is based on a cavity-enhanced Raman scattering process involving an adiabatic passage. We take into account the scattering of the pump field from the fiber, the multilevel structure of the atom, and the surface-induced van der Waals potential in describing the photon generation process. We find that, due to the confinement of the cavity field in the transverse plane of the fiber and in the space between the FBG mirrors, the probability of the generation of a single guided-mode photon can be close to unity even when the finesse of the nanofiber cavity is moderate. We show the possibilities of saturation and power broadening in the behavior of the number of photons emitted into the nanofiber.

Physical Review A•Apr 4, 2011•13 citations

Nanofiber-based all-optical switches

Fam Le Kien, Arno Rauschenbeutel

We study all-optical switches operating on a single four-level atom with the $N$-type transition configuration in a two-mode nanofiber cavity with a significant length (on the order of 20 mm) and a moderate finesse (on the order of 300) under the electromagnetically induced transparency (EIT) conditions. In our model, the gate and probe fields are the quantum nanofiber-cavity fields excited by weak classical light pulses, and the parameters of the ${D}_{2}$ line of atomic cesium are used. We examine two different switching schemes. The first scheme is based on the effect of the presence of a photon in the gate mode on the EIT of the probe mode. The second scheme is based on the use of EIT to store a photon of the gate mode in the population of an appropriate atomic level, which leads to the reduction of the transmission of the field in the probe mode. We investigate the dependencies of the switching contrast on various parameters, such as the cavity length, the mirror reflectivity, and the detunings and powers of the cavity driving field pulses. For a nanofiber cavity with fiber radius of 250 nm, cavity length of 20 mm, and cavity finesse of 313 and a cesium atom at a distance of 200 nm from the fiber surface, we numerically obtain a switching contrast on the order of about 67% for the first scheme and of about 95% for the second scheme. These switching operations require small mean numbers of photons in the nanofiber cavity gate and probe modes.

arXiv:1604.05782•Physical Review A•Jan 25, 2016•13 citations

Translational motion of an atom in a weakly driven fiber-Bragg-grating cavity

Fam Le Kien, K. Hakuta

Abstract We study the translational motion of an atom in the vicinity of a weakly driven nanofiber with two fiber-Bragg-grating mirrors. We find that the spatial dependences of the force, the friction coefficients and the momentum diffusion are very complicated due to the evanescent-wave nature of the atom–field coupling as well as the effect of the van der Waals potential. We show that the time development of the mean number of photons in the cavity closely follows the translational motion of the atom through the nodes and antinodes of the fiber-guided cavity standing-wave field even though the cavity finesse is moderate, the cavity is long and the probe field is weak.

Advances in Natural Sciences Nanoscience and Nanotechnology•May 4, 2012•1 citation
We study intracavity electromagnetically induced transparency in atoms around a nanofiber with a pair of Bragg grating mirrors. We calculate the transmission of the composite cavity-fiber-atom system and the time development of the guided probe light field. We derive analytical approximate expressions for the output probe field and its group delay. We show that the group delay of the guided light substantially depends on the input pulse length, the mirror reflectivity, the atomic number density, and the coupling field intensity. We demonstrate that the group delay of the guided light can be significantly enhanced by the presence of the fiber-Bragg-grating cavity even when the finesse of the cavity is moderate.
We study the propagation of guided light along an array of three-level atoms in the vicinity of an optical nanofiber under the condition of electromagnetically induced transparency. We examine two schemes of atomic levels and field polarizations where the guided probe field is quasilinearly polarized along the major or minor principal axis, which is parallel or perpendicular, respectively, to the radial direction of the atomic position. Our numerical calculations indicate that 200 cesium atoms in a linear array with a length of 100 $\ensuremath{\mu}\mathrm{m}$ at a distance of 200 nm from the surface of a nanofiber with a radius of 250 nm can slow down the speed of guided probe light by a factor of about $3.5\ifmmode\times\else\texttimes\fi{}{10}^{6}$ (the corresponding group delay is about 1.17 $\ensuremath{\mu}\mathrm{s})$. In the neighborhood of the Bragg resonance, a significant fraction of the guided probe light can be reflected back with a negative group delay. The reflectivity and the group delay of the reflected field do not depend on the propagation direction of the probe field. However, when the input guided light is quasilinearly polarized along the major principal axis, the transmittivity and the group delay of the transmitted field substantially depend on the propagation direction of the probe field. Under the Bragg resonance condition, an array of atoms prepared in an appropriate internal state can transmit guided light polarized along the major principal in one specific direction even in the limit of infinitely large atom numbers. The directionality of transmission of guided light through the array of atoms is a consequence of the existence of a longitudinal component of the guided light field as well as the ellipticity of both the field polarization and the atomic dipole vector.
We study spontaneous emission of an atom near a nanofiber with two fiber-Bragg-grating (FBG) mirrors. We show that the coupling between the atom and the guided modes of the nanofiber can be significantly enhanced by the FBG cavity even when the cavity finesse is moderate. We find that, when the fiber radius is 200 nm and the cavity finesse is about 30, up to 94% of spontaneous emission from the atom can be channeled into the guided modes in the overdamped-cavity regime. We show numerically and analytically that vacuum Rabi oscillations and strong coupling can occur in the FBG cavity even when the cavity finesse is moderate (about 30) and the cavity length is large (on the order of 10 cm to 1 m), unlike the case of planar and curved Fabry-Perot cavities.
We study the interaction of an atom with a quantum guided field in a weakly driven fiber-Bragg-grating (FBG) cavity. We present an effective Hamiltonian and derive the density-matrix equations for the combined atom-cavity system. We calculate the mean photon number, the second-order photon correlation function, and the atomic excited-state population. We show that due to the confinement of the guided cavity field in the fiber cross-section plane and in the space between the FBG mirrors, the presence of the atom in the FBG cavity can significantly affect the mean photon number and the photon statistics even though the cavity finesse is moderate, the cavity is long, and the probe field is weak.
We study the deterministic generation of single guided-mode photons from an atom in the vicinity of a nanofiber with two fiber-Bragg-grating (FBG) mirrors. The technique is based on a cavity-enhanced Raman scattering process involving an adiabatic passage. We take into account the scattering of the pump field from the fiber, the multilevel structure of the atom, and the surface-induced van der Waals potential in describing the photon generation process. We find that, due to the confinement of the cavity field in the transverse plane of the fiber and in the space between the FBG mirrors, the probability of the generation of a single guided-mode photon can be close to unity even when the finesse of the nanofiber cavity is moderate. We show the possibilities of saturation and power broadening in the behavior of the number of photons emitted into the nanofiber.
We study all-optical switches operating on a single four-level atom with the NNN-type transition configuration in a two-mode nanofiber cavity with a significant length (on the order of 20 mm) and a moderate finesse (on the order of 300) under the electromagnetically induced transparency (EIT) conditions. In our model, the gate and probe fields are the quantum nanofiber-cavity fields excited by weak classical light pulses, and the parameters of the D2{D}_{2}D2​ line of atomic cesium are used. We examine two different switching schemes. The first scheme is based on the effect of the presence of a photon in the gate mode on the EIT of the probe mode. The second scheme is based on the use of EIT to store a photon of the gate mode in the population of an appropriate atomic level, which leads to the reduction of the transmission of the field in the probe mode. We investigate the dependencies of the switching contrast on various parameters, such as the cavity length, the mirror reflectivity, and the detunings and powers of the cavity driving field pulses. For a nanofiber cavity with fiber radius of 250 nm, cavity length of 20 mm, and cavity finesse of 313 and a cesium atom at a distance of 200 nm from the fiber surface, we numerically obtain a switching contrast on the order of about 67% for the first scheme and of about 95% for the second scheme. These switching operations require small mean numbers of photons in the nanofiber cavity gate and probe modes.
Abstract We study the translational motion of an atom in the vicinity of a weakly driven nanofiber with two fiber-Bragg-grating mirrors. We find that the spatial dependences of the force, the friction coefficients and the momentum diffusion are very complicated due to the evanescent-wave nature of the atom–field coupling as well as the effect of the van der Waals potential. We show that the time development of the mean number of photons in the cavity closely follows the translational motion of the atom through the nodes and antinodes of the fiber-guided cavity standing-wave field even though the cavity finesse is moderate, the cavity is long and the probe field is weak.